United States immigration officials conducted operations in almost 100 7-Eleven stores on Wednesday. In the raids, they arrested at least 21 people believed to be in the counrty illegally.

Store owners were also given deadlines on when they needed to prove the employees were in the country legally by.

“The operation was the largest worksite enforcement by U.S. Immigration and Customs Enforcement, or ICE, since Republican President Donald Trump took office last January, agency spokeswoman Danielle Bennett said in an email.”

““Today’s actions send a strong message to U.S. businesses that hire and employ an illegal workforce: ICE will enforce the law, and if you are found to be breaking the law, you will be held accountable,” ICE Deputy Director Thomas Homan said in a statement.”